Note 9 - Derivative Instruments and Hedging Activities - Effect of Derivative and Hedging Activity, on Consolidated Statements of Income (Details) - Interest and Fees on Loans [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Interest Rate Swap [Member]
Derivative expense	$ 72	$ 80	$ 246	$ 172
Designated as Hedging Instrument [Member]
Derivative expense	27	29	83	66
Not Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Derivative expense	$ 45	$ 51	$ 163	$ 106